Excavator.



N 8,345. PATENTED DEC. 26 1905.

0 80 A. N. (moss.

EXGAVATOR.

APPLICATION FILED FEB. 11, 1905 3 SHEETS-$111121 1' Witne flAZeWZJZZU 7 am Inventor.

u I I PATENTED DEC. 26, 1905.

a SH-EBTS-SKEET 2.

A. N. GROSS.

EXGAVATOR.

APPLICATION FILED FEB 11 1905 M QN ZN wsw NS AZervm,

Witnesses Inventor.

pxttomegs P wk A m Am APPLICATION FILED FEB.11.1905.

3 SHEETSSHEET 3 Inventor.

Rttomegs ALBERT N. GROSS, OF TOMAH, WISCONSIN.

EXCAVATOR.

Specification of Letters Patent.

Patented Dec. 26, 1905.

Original application filed October 18, 1904, Serial No. 228,968. Divided and. this application filed February 11, 1905. Serial T0 aZZ whom it may concern.-

Be it known that I, AL ERT N. CRoss, a citizen of the United States, residing at Tomah,

This invention relates to dredging and eX-v cavating apparatus, and has for one of its objects to provide improved means for forcing the shovel into the ground and for raising and dumping the load.

A further object of the invention is to provide anovel form of give-way connection that will prevent injury to the shovel or any of the parts in case of an overload or should the shovel strike an obstruction 'which cannot be cut through or removed.

A still further object of the invention is to provide means whereby the weight of the shovel may be shifted from one to the other side of the center of the front of the shovelcar-rying frame should such adjustment be necessary or desirable.

\Vith these and other objects in view, as will more fully hereinafter appear, the invention consists in certain novel features of construction and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportions, size, and minor details of the structure may be made without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawings, Figure 1 is a side elevation of a dredging-machine constructed in accordance with the invention. Fig. 2 is a similar view of one portion of the same drawn to an enlarged scale. Fig. 3 is a plan view of that portion of the mechanism shown in Fig. 2. Fig. 4 is a transverse sec- .tional elevation of a portion of the machine on the line 44 of Fig. 3.

Fig. 5 is a plan view, partly in section, illustrating more particularly the means for adjusting and locking the lower portion of the derrick. Fig. 6 is a detail perspective view of the shovel detached. Figs. 7 and 8 are detail sectional views of the give-way connection or latch for preventing injury to 'the shovel.

Similar numerals of reference are employed to indicate corresponding parts throughout the several figures of the drawings.

The present application is a division of an application for Letters Patent for excavatingmachines filed October 18, 1904, under Serial No. 228,968. The general framework of the dredge comprises trusses 10, that are united at the front and rear by transverse sills 11, and these sills are connected bylongitudinal sills 12,the whole forming a strongly-braced structure which may be provided with a flooring of any character. The general frame and its supporting mechanism, however, form no part of the present invention, and a detailed description of the same isnot considered necessary.

At the front end of the frame is a forwardlyextended arm 62, on which is pivoted a turn= table 63, and to this turn-table is secured a fixed boom 64:, the upper end of which is connected by a tension-rod 65 and yoke 66 to the top of an A-derrick 67, the top of said derrick being connected by suitable tension members 68 to the rear transverse sill of the frame. The two standards which form the A-derrick extend down between the two transverse sills 11 at the front of the frame, as shown to the right of Fig. 4, and are connected by a transverse bar 69, the construction being such as to permit longitudinal movement of the bar and adjustment of the derrick transversely of the frame. Each of the standards or legs of the A-derrick is provided with a pair of projecting lugs or foot members 70, that slide on top of the sills l1 and prevent downward movement of the derrick.

It is desirable at times to alter the point at which the load is imposed with respect to the longitudinal center of the dredge or main frame, and for this purpose the A-derrick is made adjustable, and it may be moved transversely of the derrick-frame to any desired position. The adjustment is accomplished, preferably, by means of a rack 71, placed on the transverse bar 69, and provided with a series of teeth, with which may engage a yoke 7 2, serving to lock the rack and the derrick in any position to which it may be adjusted, the width of the spaces at the roots of the teeth being greater than the width of such spaces at the crown-line of said teeth.

One of the longitudinal bars 12 is provided with a bracket 74 at itsforward end, and to said. bracket is pivotally connected a lever 75, which may be engaged with the successive teeth of the rack in order to effect the ad j ustment of the derrick.

To the turn-table is pivoted the inner end of a vertical swinging boom 80, and to the outer end of said boom is pivoted a walkingbeam 81, carrying a shovel 82. To the shovel 82 is secured a bifurcated arm 83, that is connected by pivots 8st to the lower end of the walking-beam. To the upper end of the carrying-armig is pivoted a tooth 85, having abifurcated lower end that extends over the upper portion of the carrying-arm. The bifurcated arms of the tooth are connected by links 86 to a pin 87, and the latter is in turn connected by links 88 to a pivot 89, carried by the arm 83. Between the pivot-pin 87 and a fixed eye 90 on the rear of the shovel extends a tensionspring 91, said spring tending normally to resist movement of the tooth from the position shown in Fig. 7 to the position shown in Fig. 8, while movement in the opposite direction is prevented by a cross-bar 91, which extends between the bifurcated arms of the tooth 85 and bears against the front edge of the carrying-arm 83. To the outer end of the pivotboom 80 is pivoted a latch 92, carrying an antifriction -roller 93 for engaging the tooth 85, and to the outer end of this latch is connected a cord or cable 94:, running inboard to the dredge in convenient position to be grasped by the operator when it is desired to unlatch and dump the contents of the shovel. Should the weight or strain imposed on the shovel be in excess of the strength of the latter, the spring 91 will yield and the tooth will pass from under the antifriction-roller 93 in the manner shown in Fig. 8, automatically dumping the contents of the shovel and preventing breakage or serious strain of any of the parts.

To the eye is secured a cable or chain 95, extending over a guiding-roller 96 on the pivoted boom 80 and thence overguiding-sheaves 97, 98, and 99 to a winding-drum 100, that is connected to a suitable crank-shaft or an engine, and in operation this cable is first actuated to draw. the shovel to the rear, and by drawing the point of the tooth under the roller 93 effect the automatic latching of said shovel. To the top of the walking-beam is connected a cable 102, that extends over a guiding-sheave 103 on the outer end of the boom 64: and thence is led back over a guiding-sheave 10a, carried by a pair of links at the top of the walking-beam, and thence over guiding-sheaves 107 and 108 to a windingdrum 109, that may be driven by either hand or power, this cable being manipulated to draw the shovel forward and slightly raise the same in order to scrape the shovel along the ground and fill the same. The turn-table may then be operated in the usual manner to turn the boom and shovel to one side of the ditch being excavated, and then by pulling on the cable 94 the latch 92 will be raised and the load carried by the shovel will be dumped.

Having thus described the invention, what is claimed is 1. The combination in an excavating-machine, of a frame having a boom, an A-derrick, a guy connecting the derrick to the boom, and means for adjusting said derrick laterally of the frame and independently of the boom.

.2. In excavating-machines, an adjustablymounted derrick, a rack carried thereby, a pivoted lever for engaging successive teeth of the rack, and a locking-yoke for engaging the rack and holding the derrick in adjusted position.

8. The combination in an excavating-machine, of a frame having a pair of spaced transversely-disposed sill members, an r-derrick having a lower connecting-bar arranged between said sill members, supporting feet or lugs projecting from the derrick and engaging the upper surface of said sill members, a rack carried by the derrick, a lever for engaging the teeth of the rack and adjusting the derrick laterally of the frame, and a pivoted yoke for engaging between the teeth and locking the derrick in adjusted position.

et. in excavating machinery, a walkingbeam, a scoop or bucket pivotally connected thereto, and a yieldable latching means for holding the bucket in operative position.

5. The combination in excavating machinery, of a pivoted walking-beam. a scoopbucket pivoted thereto, a latch, a pivotallymounted pawl carried by the bucket and adapted to engage said latch, and a spring connected to the pawl and holding the same in operative position, the spring yielding under excess pressure to permit release of the pawl.

6. The combination in excavating machinery of a walking-beam, a scoop-bucket pivoted thereto, a tooth or pawl pivoted to the upper end of the bucket, a latch for engagingsaid tooth or pawl, a pair of links pivoted to the lower end of the tooth, a second pair of links forming a connection between the first pair and the mounted frame, and a tension-spring extending between the connected links and a fixed point, thereby to permit yieldingof the tooth or pawl when the scoop- 

